The US Air Force (USAF) plans to phase out the Northrop Grumman RQ-4 Global Hawk surveillance drone by the end of 2027. 

The information was revealed in an USAF letter to Northrop Grumman, obtained by Breaking Defense. 

The letter stated that the current fleet of RQ-4s will reach the end of its life in 2026. However, a USAF spokesperson clarified that the service plans to shut down RQ-4 operations in the financial year 2027. 

The letter concerns the RQ-4 Block 40, the latest modification of the aircraft, hinting at the fact that no further improvements to it are going to be made.  

The RQ-4 is a high-altitude, long endurance unmanned aircraft that entered service in 1998 and remained one of the primary surveillance and reconnaissance aircraft for the USAF. 

It can carry up to 1,360 kilograms (3,000 pounds) of payload and remain airborne for up to 30 hours.  

The type has also been acquired by South Korea and Japan, while two aircraft have been transferred to NASA for high-altitude tests.